At the moment there are over 3700 tulips registered and so to
make the lists more manageable and also give them a better load
time for your browser, I've split them into lists for each tulip color.
Lots of tulips are of mixed color and the lists below show tulips
with at least the named list color.
e.g the cream list will show tulips that have cream as
either its main color or cream as a secondary color.
The following lists are in color / flowering time / name